Case shift mechanism for typewriting machines



March 21, 1950 J. 'F. KOCA 2,501,605

CASE SHIFT MECHANISM FOR TYPEWRITING MACHINES Original Filed Jan. 25, 1945 4 Sheets-Sheet 1 g 0 8 O O O O 8 O O O O E? 8 0612757 1 @02 5 fjdbea J. F. KOCA March 21, 1950 CASE SHIFT MECHANISM FOR TYPEWRITING MACHINES 4 SheetS Sheet 2 Original Filed Jan. 25,1945

FIE/@7275? J/mis ffloca J. F. KOCA March 21, 1950 CASE SHIFT MECHANISM FOR TYPEWRITING MACHINES 4 Sheets-Sheet 3 Original Filed Jan. 25, 1945 ',77Z U6/z/07 James fjfoca,

J. F. KOCA March 21, 1950 CASE SHIFT MECHANISM FOR TYPEWRITING MACHINES 4 Sheets-Sheet '4 Original Filed Jan. 25, 1945 I five/2757* kfalzzcls floca Patented Mar. 21 1950 CASE SHIFT MECHANISM. FOR TYPEWRITING MACHINES James F. Koca, Woodstock, 111;, assignor to Woodstock Typewriter Company, Woodstock, 111., a corporation of Illinois Original application January 25, 1945, Serial No. 574,568. Divided and this application May 16, 1947, Serial N0. 748,718

12 Claims.

This invention relates to typewriters, and its primary object is the provision of new and improved means for effecting shiftable movement of the type bar segment, and for locking the segment in its shifted position, and this application is a division of my application, Serial Number 574,568, filed January 25, 1945..

Another object is the provision of a new and improved mechanism for shifting the type bar segment of a typewriter, and the provision of a new and improved key lever action for effecting the shifting of the type bar for writing engagement with the platen.

A further object is the provision of. means for locking the shift key lever action of a typewriter provided with a new and improved type bar segment, and to effect unlocking of the device upon the depression of a shift key lever.

A further object is to provide a new and improved shift key lever construction for eliecting displacement of a shiftable type bar segment, the parts being juxtaposed and in close assembled, relationship, to effect saving of space and to make the assembly compact.

A still further object of the invention is the provision of a shiftable type bar segment so positioned with respect to certain other operating parts of the machine that the printing action with respect to the. platen is relatively close to the vertical center line of the type bar segment.

Still another object is the provision of a new and improved key lever and shift key construction, whereby easy action is obtained while maintaining proper acceleration, the shifting of the type bar segment being considerably easier than the shifting of the platen, to accomplish the same result, whereby no greater pressure is required for shifting the type bar segment than is required in operating key levers of conventional design and construction.

To the attainment of these ends, and the accomplishment of other new and useful objects as will appear, the invention consists in the features. of novelty in substantially the construction, combination and arrangement of the several parts, hereinafter more fully described and claimed, and shown in the accompanying drawings, in which Fig. 1 is a detail plan sectional view, showing the shift key mechanism and type bar segment mechanism, certain parts being omitted for the sake of clearness.

Fig. 2 is a detail vertical sectional view on line 2-2, Fig. 1, certain parts being omitted for the sake of clearness.

Fi 3 is a detail end elevation, partly in section, looking in the direction of the arrows 3-3, Fig. l, and showing certain of the mechanism related to the shift key and the type bar segment.

Fig. 4 is a detail fragmentary view looking in the direction of the arrows 4-4 of Fig. 1, showing the shift key and key lever mechanism or parts in elevation, and the manner in which the same are arranged with respect to the type bar segment, type bar, and platen.

Fig. 5 is a fragmentary end elevation of the type bar carrier lock mechanism in its normal .position.

Fig. 6 is a detail fragmentary end elevational view, showing the shift key mechanism and associated parts, the shift key lever being shown in normal non-depressed position.

Fig. '7 is a view similar to Fig. 6, but showing the shift key and shift key lock in engagement.

Fig. 8 is a detail fragmentary View showing in elevation, a modified form of type bar segment carrier locking arrangement.

The particular typewriter herein shown for the purpose of illustrating the present invention, is the popular and Well-known Woodstock typewriter, although the invention is not confined to this particular make of typewriting machine.

The typewriter includes a shiitable type bar segment 2, upon which there is operatively mounted type bars 3., carrying type heads 4, there being improved means for shifting the segment from normal position for printing the lower case letters 5 on the type head, to a lower position for printing the capital letters 6 of the type head 4.

The case shift for shifting the type bar segment 2 includes a shift key I, having a shift key lever 8 terminating in a downwardly integral extension 9, which is pivotally mounted at I0, to a part on the machine main frame. A link II is pivotally connected to an upwardly projecting extension integral with the shift key lever 8 (Figs. 4 to- 7). A spring I2 is connected to the link II, and to the extension, and normally urges the link I I into pro-per position With respect I to the assembly. The link II is provided with an elongated slot I3 at its forward end, in which slot there is received a pin I4, on the extension 9 of the shift key lever 8.

The rear end of the link II is pivotally connected to a bell crank I5, by means of a pin and slot connection, there being a slot I6 formed in the end of the link I I, the slot being engaged by a pin I! on the upwardly extending arm I8 of the bell crank I5 (Fig. 5-). The bell crank I5 is pivotally mounted at I9, to a part of the sub-frame 3 of the typewriter (Figs. 6 and '7). The lower, forwardly extending arm 2| of the bell crank |5 has has pivotally connected thereto, as at 22, the tail piece 23 of the segment carrier 24.

The segment carrier 24 has mounted on each side thereof, a guide 25 provided with a V-shaped notch (Fig. 2), which co-operates with a similar guide 25 having a V-shaped notch formed therein. The opposed V-shaped notches form a guideway to receive ball bearings 21, whereupon the type bar Segment 2 is adapted to have vertical slidable movement. The guide 26 is secured to a part 28 on the typewriter frame, the guide 26 being secured to the part 28 by means of screws 29 (Fig. 2). Adjusting screws 30, 3B are provided to eifect proper vertical alinement of the guides 26 with respect to their co-operating guides 25.

The type bar segment 2, therefore, is free to have vertical slidable movement, there being an extension spring 3| connected to a pin 32 on a part of the machine frame, and to an extension 33 formed on the end of the arm 2| of the bell crank I5. The type bar segment 2 is normally held in its upward position by the spring 3|, but is adapted to be lowered upon the depression of the shift key I, which causes downward pull on the spring 3|, to bring the capital letter to be printed into proper printing position with respect to the platen.

The vertical slidable or shiftable movement of the segment 2 is limited by limiting fingers 34, arranged on both sides of the carrier 24, being preferably made of steel, and preferably having some resiliency. Each limiting finger 34 may comprise two separate parts, 35 and 36, which are secured in position by screws 3'! and 38, respectively. Each limiting finger 34 is positioned between ears 39 and 40. Set screws 4| and 42 extend through the ears 39 and 40, respectively, to limit the movement of the limiting finger 34. Inasmuch as the limiting finger 34 is secured to the segment carrier 24, the vertical slidable movement of the type bar segment 2 will be limited by the position of the adjusting screws 4| and 42.

The spring 3| is adapted to hold the segment 2 in its uppermost position, with the limiting finger 34 in engagement with the under side of the adjusting screw 4|, which acts as a stop. The segment 2 is adapted to be lowered by the depression of the shift key I, which will cause rotative movement of the bell crank 5 about its pivot l9, causing downward movement of the segment 2, and extension of the spring 3|. A release of the shift key I will permit the spring 3| to return the parts to their normal position, which is the upward position of the segment 2, as shown in Fig. 3.

Means are provided to retain the parts in their normal operative position as shown in Fig. 3, and this means comprises a locking means of toggle formation and embodying a pair of links 43, which are pivotally connected at 44, to the arm I8 of the bell crank l5, a bell crank 45, which has its end extending between the spaced links 43, being pivoted to the links 43, as at 46. The bell crank 45 is pivotally mounted on a part of the machine frame by an eccentric pin 41, whereby free adjustment may be had (Figs. 4 and '7).

The bell crank 45 includes a stop 48, which is adapted to co-operate with a stop 49 on the arm |8 of the bell crank l5. A pin 50 on the link H is adapted for engagement with the arm 5| of the bell crank 45, whereupon depression of the shift key 1 will move the link toward the left (Fig. 4) a distance equal to the length of the slot |5 (Fig. 5), causing the locking stop 48 (Fig. '7) to be moved from stop 49, against the tension of spring 53.

In normal position, the links 43, and the lower arm of the bell crank 45, are in a straight line (Fig. 3), and thus form a lock, which is broken upon the depression of the shift key (Fig. 7). The spring 53 normally holds the parts in locked position, the stops 48 and 45 maintaining the parts in such straight line position. The spring 52 maintains the pin 55 normally away from the arm 5| of the bell crank 45, the spring 53 being for the purpose of maintaining the links 43, and bell crank 45, in their normal locking position.

The shift key 1, when first depressed, will move the link H to the left (Figs. 4, 5 and 6), by reason of the pin and slot connection |5|| with the arm 58 of the bell crank l5, whereupon the pin 55 will engage the arm 5| of the bell crank 45, causing the straight line locking engagement to be broken, whereupon the links 43, and the lower arm of. the bell crank 45, will assume a position approximating the position shown in Fig. 7. That is, the toggle formed by the links 43, 45 will knuckle. The bell crank l5 will then be free to move on its pivot I9, upon further depression of the shift key and the parts will then assume the position shown in Fig. '7, the type bar segment 2 being in its lowermost position, whereby a cap ital letter may be printed.

The locking arrangement shown in Fig. 8 dispenses with the connection extending beyond the arm 5| of the bell crank 45.

In Fig. 8, the bell crank 45a, corresponding to the bell crank 45 (Fig. '7), has its arm 5w. pivotally connected at 54a, to the link so that when the shift key is depressed, the bell crank 45a will be swung on its pivot 41a, so as to break the locking connection between links 430. and bell crank 45a. The spring 5311 is connected to the links 4311, and to the arm 5|a of the bell crank 45a, for the same purpose as the spring 53 shown in Figs. 6 and '7, and the shoulder or stop 48a on the bell crank 45a co-operates with the shoulder or stop 430. on the arm N3 of the bell crank l5, for the same purpose as the similar parts shown in Fig. '7.

While the mounting and operation of the type bar 3 constitutes the subject matter of my copending application heretofore referred to, a brief description thereof is here given so that the co-operation between the type bar and the type bar segment will be clearly understood, reference being had particularly to Fig. 4.

Key levers 55, having keys 56, are pivotally and detachably mounted, as at 56a, in a part of the machine sub-frame 20, there being a spring 51 to normally hold the key levers 55 in their normal upward position. Each key lever 55 has pivotally connected thereto, by means of a slot and pin connection 60, a bell crank or sub-lever 6|, which is pivotally mounted at 62, to a part of the sub-frame 2B. The bell crank is connected by a link 63, to an arm 54, which is pivotally mounted on the segment carrier 24.

A second link 65 is pivotally connected to the arm 64, and to a tail piece 61 on the end of the type bar 3, whereupon the lower case letters 5, 0n the type bars 3, will come into printing engagement or contact with the platen 58, when the key 56 is depressed. The capital letters 6 on the type head 4 of the bar 3, are adapted to be brought into printing engagement when the shift key 1 is depressed, first to move the type bar 3, links 66, and arms 64 downwardly, where-,

azsone'oe upon subsequent depressions of keys 56 on key levers 55, will cause a capital letter '6, on a type bar, 'to come into printing contact with the platen =68.

The assembly of the parts 64 and 66 with respect to the type bar 3 and the segment carrier 24, comprises .a unit, as the carrier 24 supports the type bar 3 and the segment 2. Thus, during assembly, the segment '2, with its co-operating pivotally mounted type bar 3 and its co-operating parts, may be assembled, as a unit, on the carrier, because the arm 64 is connected to the carrier, and the link '66 connects the type bar 3 with the arm 64. The depression of the shift key, therefore, causes the segment 2, the type bar 3, the link :66, andthe arm 54 to move downwardly, without in any way affecting the key lever 55, as any movement between the type bar and the key lever 55 will be taken up between the pivotal connection of the .link 63 with the arm 64, and the pivotal connection between the link 63 and the bell crank 61.

The platen 68 is of the usual type, in that it has slida'ble transverse movement on ways 69. However, the platen is not raised as in conventional machines, to effect printing of capital letters, as shifting of the platen is no longer necessary, because the type bar segment is shifted. The invention, therefore, provides for shifting the type bar segment to cause case shifting, instead of shifting the platen.

The shift key levers 8 and 83 may each be provided with an upwardly extending portion 10 (Fig. '4), which acts as a stop adapted for engagement with the edge ll of a comb-shaped member 12. The lower end of the levers 8 and 83 may also be provided with a guide extension 73, for guiding the levers in the slots of the member 12, preventing lateral movement thereof, the member 12 being secured to a bracket 14, secured to the main frame (Fig. 3).

The key lever B may be provided with a shift lock 75 '(Figs. 4, 6 and '7), which is pivotally mounted, as at 16, on the key lever B, there being a'pin H on the shift key lever, engaging in a slot 78 formed on the shift lock 15. The shift lock 15 is provided with a locking end 19, which is adapted to have locking engagement with a keeper member 80, secured to the sub-frame of the machine. A spring 81 is adapted to hold the shift lock in its normal inactive position, and to return the locking member 19 when the shift lock is disengaged from its 'co-operating locking member 86.

A second shift key 82 (Fig. 1) is adapted to be mounted on the left-hand side of the machine, and this latter shift key includes a shift key lever 83, which is rigidly secured to a cross bar 84, the cross bar being also rigidly connected to the shift key lever 8, whereupon the type bar segment 2 may be operated by the depression of either the shift key 1 or the shift key 82. The shift key 82 may, if desired, be provided with a shift look (not shown), similar to the shift lock J5.

While the preferred form of the invention has been herein shown and described, it is to be understood that various changes may be made in the details of construction, and in the combination and arrangement of the several parts, within the scope of the claims, without departing from the spirit of this invention.

What is claimed as new is:

l. A typewriter comprising a frame and a shiftable type bar segment, means to maintain said segment in a predetermined position, mechanism for case shifting said segment, locking means for holding said segment in said predetermined position, said locking means including a toggle arm and a link interposed between said case shifting mechanism and the frame, and stop means on the toggle arm and on a part of the case shifting mechanism, for determining the locking position of said toggle arm and link.

2. A typewriter comprising a frame structure, a shifta'ble segment carrier, mechanism for shifting said carrier, a shift key to operate said mechanism, said mechanism including a bell crank pivotally mounted on said frame structure and connected to the carrier and the shift key, means for holding the carrier in a predetermined position, locking means to lock the carrier in said position including a toggle joint between said bell crank and said frame structure, and means operated by said shift key to unlock said locking means prior to shifting the carrier.

3. A typewriter embodying a frame structure and a shiftable type bar segment carrier, a depressible key member pivoted to a part of said structure, a bell crank pivotally mounted to a part of said structure and connected to said carrier, a link connecting the key member to the bell crank, a type bar segment carried by said carrier, type bars operatively connected to said segment, said type bars being shiftable with said segment by said key member, means for locking the segment in operable position including a second bell crank and a second link connected between said first named bell crank and said second bell crank, and means to unlock said locking means upon depression of the said key member.

4.2 typewriter embodying a type bar segment, resilient means to maintain said segment in a predetermined position, mechanism embodying an operating key and a bell crank for case shifting said segment, locking means for holding said segment in a predetermined position, said looking means embodying a toggle joint for maintaining the bell crank against operation by the key,

means operatively connected to said key and operating to break said joint, whereby the said segment may be shifted against the stress of the first said means, the said joint-breaking means embodying a link disposed between the key and said bell crank, a projection on one of the link members of the toggle fjoint,,and means on said link adapted to engage said projection to rock the toggle joint member in advance of movement of said segment by said key.

5. A typewriter embodying a type bar segment, means operating normally to maintain said segment in a predetermined position, mechanism for case shifting said segment, said mechanism embodying a bell crank, one arm of which is openatively connected to said segment, an operating key, a link operatively connecting said key with the other arm of said bell crank, means for looking said bell crank against operation by said key, said locking means embodying a toggle joint between said bell crank and a fixed support, and inter-engaging means between one of the members of said toggle and the said link, whereby upon operation of said key, said togglewill be actuated to unlock the bell crank, and said bell crank will be subsequently actuated to shift said segment.

.. '6. A typewriter embodying a type bar segment,

means operating normally to maintain said segment in a predetermined position, mechanism for case shifting said segment, said mechanism embodying a bell crank, one arm of which is operatively connected to said segment, an operating key, a link operatively connecting said key with the other arm of said bell crank, means for locking said bell crank against operation by said key, said locking means embodying a toggle joint between said bell crank and a fixed support, and interengaging means between one of the members of said toggle and the said link, there being a loose connection between said link and the said bell crank, whereby upon operation of said key, said toggle will be actuated to unlock the bell crank, and said bell crank will be subsequently actuated to shift said segment.

'7. A typewriter embodying a type bar segment, resilient means to maintain said segment in a predetermined position, mechanism embodying an operating key and a bell crank for case shifting said segment, locking means for holding said segment in a predetermined position, said locking means embodying a toggle joint operatively connected to said bell crank, interengaging means between said bell crank and one member of the toggle joint for maintaining the joint against knuckling and for maintaining the bell crank against operation by the key, and means operatively connected to said key and operating to break said joint, whereby the said segment may be shifted against the stress of the first said means.

8. A typewriter embodying a type bar segment, means tending normally to maintain said segment in a predetermined position, mechanism for case shifting said segment, said mechanism embodying a bell crank, means operatively connecting one end of said bell crank to said segment, an operating key, a link having connection at one end to said key, a loose connection between the other end of said link and the other end of said bell crank, resilient means between said link and the last said end of the bell crank and operating to move said link in one direction with respect to the bell crank, locking means for looking said bell crank against operation by said key, and means on said link for rendering said locking means inoperative in advance of the movement of said bell crank by said key.

9. A typewriter embodying a type bar segment, means tending normally to maintain said segment in a predetermined position, mechanism for case shifting said segment, said mechanism embodying a bell crank, means operatively connecting one end of said bell crank to said segment, an operating key, a link having connection at one end to said key, a loose connection between the other end of said link and the other end of said bell crank, resilient means between said link and the last said end of the bell crank and operating to move said link in one direction with respect to the bell crank, locking means for locking said bell crank against operation by said key, said locking means embodying a toggle joint, one end of which is connected to said bell crank and the other end to a fixed support, resilient means for holding the joint in locking condition, an arm on one of the members of the joint, and a projection on said link for engagement with said arm, whereby to render said locking means inactive by the operation of said key, and to also permit operation of the bell crank by said key.

10. A typewriter embodying a type bar segment, means tending normally to maintain said segment in a predetermined position, mechanism for case shifting said segment, said mechanism embodying a bell crank, means operatively connecting one end of said bell crank to said segment, an operating key, a link having connection at one end to said key, a loose connection between the other end of said link and the other end of said bell crank, resilient means between said link and the last said end of the bell crank and operating to move said link in one direction with respect to the bell crank, locking means for looking said bell crank against operation by said key, said locking means embodying a toggle joint between the bell crank and a fixed support, interengaging means between one toggle member and said bell crank for limiting the relative movement of the toggle memberin one direction, resilient means tending normally to maintain the last said means in engagement, an arm on one of said toggle members, and a projection on said link adapted to engage said arm upon operation of said key, to render the locking means inactive and to permit actuation of said bell crank by said key, to shift said type bar segment.

11. A typewriter embodying a type bar segment, means tending normally to maintain said se ment in a predetermined position, mechanism for case shifting said segment, said mechanism embodying a bell crank, a connection between one end of said bell crank and said segment, an operating key, a link having connection at one end to said key, a loose connection between the other end of said link and the other end of said bell crank, resilient means between said link and the last said end of the bell crank and operating to move said link i one direction with respect to the bell crank, locking means for locking said bell crank against operation by said key, and means on said link for rendering said locking means inoperative in advance of the movement of said bell crank by said key.

12. A typewriter embodying a type bar segment, means tending normally to maintain said segment in a predetermined position, mechanism for case shifting said segment, said mechanism embodying a bell crank, means operatively connecting one arm of said bell crank with said segment, an operating key, a connecting link between said key and the other arm of said bell crank, means embodying a toggle joint for locking the bell crank against operation by said key, one end of said joint being operatively connected with said bell crank, an adjustable connection between the other end of the toggle joint and a fixed support, an arm on one of the toggle joint members, and a projection on the said link, whereby upon operation of said key, said projection will engage said arm and operate to break said joint, to permit shifting of said segment by the said key.

JAMES F. KOCA.

REFERENCES CITED The following references are of record in the file of this patent:

Thompson July 14, 1942 

